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  <title>The Hashable interface</title>
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 <h1 class="title">The Hashable interface</h1>
 

 <div class="partintro"><p class="verinfo">(No version information available, might only be in Git)</p>


  <div class="section" id="ds-hashable.intro">
   <h2 class="title">简介</h2>
   <p class="para">
        Hashable is an interface which allows objects to be used as keys.
        It’s an alternative to <span class="function"><a href="function.spl-object-hash.html" class="function">spl_object_hash()</a></span>,
        which determines an object’s hash based on its handle:
        this means that two objects that are considered equal by an implicit
        definition would not treated as equal because they are not the same instance.
   </p>
   <p class="para">
        <span class="function"><a href="function.hash.html" class="function">hash()</a></span> is used to return a scalar value to be used as
        the object&#039;s hash value, which determines where it goes in the hash table.
        While this value does not have to be unique, objects which are equal must
        have the same hash value.
    </p>
    <p class="para">
        <span class="function"><strong>equals()</strong></span> is used to determine if two objects are equal.
        It&#039;s guaranteed that the comparing object will be an instance of the same class
        as the subject.
    </p>

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   <h2 class="title">接口摘要</h2>


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    <div class="ooclass"></div>


    <div class="classsynopsisinfo">
     <span class="ooclass">
      <span class="modifier">class</span> <strong class="classname">Ds\Hashable</strong>
     </span>
     {</div>


    <div class="classsynopsisinfo classsynopsisinfo_comment">/* 方法 */</div>
    <div class="methodsynopsis dc-description">
   <span class="modifier">abstract</span> <span class="modifier">public</span> <span class="methodname"><a href="ds-hashable.equals.html" class="methodname">equals</a></span>(<span class="methodparam"><span class="type">object</span> <code class="parameter">$obj</code></span>): <span class="type">bool</span></div>
<div class="methodsynopsis dc-description"><span class="modifier">abstract</span> <span class="modifier">public</span> <span class="methodname"><a href="ds-hashable.hash.html" class="methodname">hash</a></span>(): <span class="type"><a href="language.types.declarations.html#language.types.declarations.mixed" class="type mixed">mixed</a></span></div>

   }</div>


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<h2>目录</h2><ul class="chunklist chunklist_reference"><li><a href="ds-hashable.equals.html">Ds\Hashable::equals</a> — Determines whether an object is equal to the current instance</li><li><a href="ds-hashable.hash.html">Ds\Hashable::hash</a> — Returns a scalar value to be used as a hash value</li></ul>
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